The international T2K Collaboration strengthened its previous hint that the symmetry between matter and antimatter may be violated for neutrino oscillation. A preliminary analysis of T2K’s latest data rejects the hypothesis that neutrinos and antineutrinos oscillate with the same probability at 95% confidence (2σ) level. With nearly twice the neutrino data in 2017 compared to their 2016 results, T2K has performed a new analysis of neutrino and antineutrino data using a new event reconstruction algorithm for interactions in the far detector, Super-Kamiokande. Today’s announcement was made by Prof Mark Hartz, of the University of Tokyo Kavli Institute for the Physics and Mathematics of the Universe (Japan) and TRIUMF (Canada), who presented the results at a colloquium at the High Energy Accelerator Research Organization (KEK) in Tsukuba, Japan.

To read the full press release, go to website link below.

Kavli IPMU Project Assistant Professor Mark Hartz is a co-convener of the neutrino oscillation analysis working group in the T2K collaboration and has been involved in the data analysis effort of T2K. His reaction to this announcement is as follows:

"By doubling our neutrino mode data and making analysis improvements, T2K has made the most sensitive search for CP violation in neutrino oscillations yet. This data shows an intriguing hint of CP violation. To make a definitive measurement, T2K will need to collect additional neutrino mode and antineutrino mode data. As a T2K collaborator, I am excited to continue our long-term program to search for CP violation in neutrino oscillations and make precision neutrino oscillation parameter measurements."